The present invention provides an agent for improving taste of tea drinks, comprising at least one glyceroglycolipid, preferably monogalactosyl diacylglycerol or digalactosyl diacylglycerol, as an active ingredient. The agent of the present invention is for use to enhance kokumi, to mask astringent taste, and to prevent precipitates. The agent of the present invention is effective especially in improving tea drinks containing ground tea leaves. The present invention also provides a method for producing tea drinks containing ground tea leaves and at least 1.0 µg/ml of glyceroglycolipids and having an absorbency of 0.25 or below at 680 nm, and tea drinks containing glyceroglycolipid, which method comprises grinding tea leaves into an average particle size of 1-100 µm (preferably 1-50 µm, more preferably 1-20 µm), and mixing the resulting ground tea leaves with neutral (pH 5-7, preferably 5.5-7, especially preferably 6-7) water to elute the glyceroglycolipids into the water.